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cosmology

(Encyclopedia)cosmology, area of science that aims at a comprehensive theory of the structure and evolution of the entire physical universe. The earliest pre-Ptolemaic theories assumed that the earth was the cent...

interest

(Encyclopedia)interest, charge for the use of credit or money, usually figured as a percentage of the principal and computed annually. Simple interest is computed annually on the principal. Compound interest, paid ...

psychoanalysis

(Encyclopedia)psychoanalysis, name given by Sigmund Freud to a system of interpretation and therapeutic treatment of psychological disorders. Psychoanalysis began after Freud studied (1885–86) with the French neu...

correspondence principle

(Encyclopedia)correspondence principle, physical principle, enunciated by Niels Bohr in 1923, according to which the predictions of the quantum theory must correspond to the predictions of the classical theories of...

Fisher, Irving

(Encyclopedia)Fisher, Irving, 1867–1947, American economist, b. Saugerties, N.Y., Ph.D. Yale, 1891. He began teaching at Yale in 1890 and was active there until 1935. His earliest work was in mathematics, and he ...

Nash, John Forbes, Jr.

(Encyclopedia)Nash, John Forbes, Jr., 1928–2015, American mathematician, b. Bluefield, W.Va., grad. Carnegie Institute of Technology (now Carnegie-Mellon Univ., B.A. and M.A. 1948), Ph.D. Princeton 1950. During a...

Gauss, Carl Friedrich

(Encyclopedia)Gauss, Carl Friedrich kärl frēˈdrĭkh gous [key], born Johann Friederich Carl Gauss, 1777–1855, German mathematician, physicist, and astronomer. Gauss was educated at the Caroline College, Brunsw...

aggression

(Encyclopedia)aggression, a form of behavior characterized by physical or verbal attack. It may appear either appropriate and self-protective, even constructive, as in healthy self-assertiveness, or inappropriate a...

light

(Encyclopedia)light, visible electromagnetic radiation. Of the entire electromagnetic spectrum, the human eye is sensitive to only a tiny part, the part that is called light. The wavelengths of visible light range ...

evolution

(Encyclopedia)CE5 Plant and animal evolution [Modified from Alfred Gunderson in Brooklyn Botanic Garden Leaflets, Ser. 18, No. 4 (1930); used by permission.] evolution, concept that embodies the belief that ex...